Compass app (#2446)

compass_app/app/lib/ui/home/view_models/home_viewmodel.dart

@@ -0,0 +1,95 @@
+// Copyright 2024 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter/foundation.dart';
+import 'package:logging/logging.dart';
+
+import '../../../data/repositories/booking/booking_repository.dart';
+import '../../../data/repositories/user/user_repository.dart';
+import '../../../domain/models/booking/booking_summary.dart';
+import '../../../domain/models/user/user.dart';
+import '../../../utils/command.dart';
+import '../../../utils/result.dart';
+
+class HomeViewModel extends ChangeNotifier {
+  HomeViewModel({
+    required BookingRepository bookingRepository,
+    required UserRepository userRepository,
+  })  : _bookingRepository = bookingRepository,
+        _userRepository = userRepository {
+    load = Command0(_load)..execute();
+    deleteBooking = Command1(_deleteBooking);
+  }
+
+  final BookingRepository _bookingRepository;
+  final UserRepository _userRepository;
+  final _log = Logger('HomeViewModel');
+  List<BookingSummary> _bookings = [];
+  User? _user;
+
+  late Command0 load;
+  late Command1<void, int> deleteBooking;
+
+  List<BookingSummary> get bookings => _bookings;
+
+  User? get user => _user;
+
+  Future<Result> _load() async {
+    try {
+      final result = await _bookingRepository.getBookingsList();
+      switch (result) {
+        case Ok<List<BookingSummary>>():
+          _bookings = result.value;
+          _log.fine('Loaded bookings');
+        case Error<List<BookingSummary>>():
+          _log.warning('Failed to load bookings', result.error);
+          return result;
+      }
+
+      final userResult = await _userRepository.getUser();
+      switch (userResult) {
+        case Ok<User>():
+          _user = userResult.value;
+          _log.fine('Loaded user');
+        case Error<User>():
+          _log.warning('Failed to load user', userResult.error);
+      }
+
+      return userResult;
+    } finally {
+      notifyListeners();
+    }
+  }
+
+  Future<Result<void>> _deleteBooking(int id) async {
+    try {
+      final resultDelete = await _bookingRepository.delete(id);
+      switch (resultDelete) {
+        case Ok<void>():
+          _log.fine('Deleted booking $id');
+        case Error<void>():
+          _log.warning('Failed to delete booking $id', resultDelete.error);
+          return resultDelete;
+      }
+
+      // After deleting the booking, we need to reload the bookings list.
+      // BookingRepository is the source of truth for bookings.
+      final resultLoadBookings = await _bookingRepository.getBookingsList();
+      switch (resultLoadBookings) {
+        case Ok<List<BookingSummary>>():
+          _bookings = resultLoadBookings.value;
+          _log.fine('Loaded bookings');
+        case Error<List<BookingSummary>>():
+          _log.warning('Failed to load bookings', resultLoadBookings.error);
+          return resultLoadBookings;
+      }
+
+      return resultLoadBookings;
+    } finally {
+      notifyListeners();
+    }
+  }
+}